Editing Interstate 465 (section)

===Initial construction (1959–1970)===
The I-465 beltway was constructed in segments. There were 16&nbsp;segments along the original proposed semicircumferential alignment between [[Interstate 65 in Indiana|I-65]] in [[Boone County, Indiana|Boone County]] at exit&nbsp;129 and that same highway {{Convert|6|mi|km|abbr=|spell=in}} to the south at exit&nbsp;123 in [[Marion County, Indiana|Marion County]]. Indiana highway officials recognized the value of having the route be a full circumferential, so using non-Interstate federal funding and employing a temporary designation of SR&nbsp;100, they planned a separate 17th segment northward between I-65 at its exit&nbsp;123 and the north leg of I-465 in Boone County. By the time that added section was completed in 1970, Indiana had obtained federal approval to sign it as I-465 as well, resulting in the creation of a dogleg section of I-465 outside of the loop (now signed as [[Interstate 865|I-865]]).<ref name=Ripple1975 />

State highway officials concentrated on building the west and south legs of I-465 early in the overall project, since they were the missing portions of the SR&nbsp;100 concept. Construction began in 1959, and the first section of the I-465 beltway to be completed was the portion on the west leg between I-65 near [[Eagle Creek Park]] and I-74/[[U.S. Route 136 in Indiana|US&nbsp;136]] in [[Speedway, Indiana|Speedway]]. That section was opened to traffic on September&nbsp;26, 1961, simultaneously with the adjacent section of I-65 northwest from there running {{convert|1.48|mi|km}} to 71st Street. By July&nbsp;18, 1962, all four segments of the original west leg were open between [[Indiana State Road 67|SR&nbsp;67]] (Kentucky Avenue) and I-65, but the interchange with [[Interstate 70 in Indiana|I-70]] in that stretch was not completed until much later that decade when the segment of that route from I-465 west to [[Indiana State Road 43|SR&nbsp;43]] opened in 1968.<ref name=Ripple1975 />

The south side sections were the next to be completed, with three opening in the second half of 1963 and two more on October&nbsp;15, 1964. This completed both the south leg and the first segment of the east leg and included a connection from a point just north of the Raymond Street grade separation to SR&nbsp;100 (Shadeland Avenue) at Washington Street ([[U.S. Route 40 in Indiana|US&nbsp;40]]). With these sections open, the full length of I-74's concurrency over I-465 was now available for motorists. The south leg's junction with I-65 was also completed, but I-65 itself was open only between a temporary intersection at Thompson Road to the south and the Keystone Avenue interchange {{convert|1.18|mi|km}} north of I-465 until early 1971.<ref name=Ripple1975 />

With SR&nbsp;100/Shadeland Avenue connected to the full southern and western bypass of Indianapolis, work on I-465's east leg slowed, delaying the opening of the next segment over three years. In January&nbsp;1968, two sections of the east leg, between [[U.S. Route 36 in Indiana|US&nbsp;36]]/[[Indiana State Road 67|SR&nbsp;67]] (Pendleton Pike) and the SR&nbsp;100 junction near Raymond Street, were completed and opened a day apart. This allowed through traffic from both US&nbsp;36 and SR&nbsp;67 to bypass the increasingly congested SR&nbsp;100. The interchange with [[Interstate 70 in Indiana|I-70]] in this newly opened section was not yet complete, and its ramps did not open until the opening of that route's mainline between SR&nbsp;100/Shadeland Avenue and [[Indiana State Road 9|SR&nbsp;9]] near [[Greenfield, Indiana|Greenfield]] on December&nbsp;2 of that year. On October&nbsp;23, 1968, the section of I-465 between Pendleton Pike and 56th Street at Shadeland Avenue was finished and opened to traffic, completing the east leg's eastern bypass of SR&nbsp;100.<ref name=Ripple1975 />

With its alignment controversies now settled, the north leg of I-465 began to take shape in the late 1960s. The section between [[U.S. Route 421|US&nbsp;421]] (Michigan Road) and [[U.S. Route 31 in Indiana|US&nbsp;31]] (Meridian Street) was the first on this side of town to see traffic on October&nbsp;20, 1968. A year to the day later, the segment from US&nbsp;31 to Keystone Avenue (then [[Indiana State Road 431|SR&nbsp;431]]) was opened to motorists. The next month, in November&nbsp;1969, the north extension of the west leg was completed and signed as I-465 (although it was considered to be "added mileage" by the [[Federal Highway Administration]] (FHWA) since it was built to Interstate standards using non-Interstate funds by Indiana), but only the portion between I-65 and 86th Street was opened to traffic because the segment of the north leg to which it would connect was not yet complete. That occurred on August&nbsp;18, 1970, when the western end of the north leg between I-65 near Royalton and Michigan Road (US&nbsp;421) was finished and opened to traffic. At that time, the final connection on the north extension of the west leg to 86th Street was also opened, leaving only one remaining gap in the entire I-465 route.<ref name=Ripple1975 />

The final section of I-465 to be built was the portion joining the north and east legs between Keystone Avenue (then SR&nbsp;431) and 56th Street at Shadeland Avenue (then SR&nbsp;100). This stretch opened to traffic on October&nbsp;5, 1970, and marked the completion of the I-465 beltway around Indianapolis.<ref name=Ripple1975 />